Can I zone 3PAR disk and LTO5 tape drives on the same HBA?

[StuartA46]

All:

In the old days we used to have 3 HBAs on a server:  2 x HBAs to disk and 1 x HBA to tape.  all on the SAN, of course.  The theory was that disk and tape I/O on the same HBA would slow I/O.  Is this still true in 2016?  Both for Windows and for RHEL Linux.

     Stuart

[Torsten.]

Still true, why not?

Both disks and tape need even more bandwith.

[madkiwi]

Yes you can but the I/O profiles of disk and tape when they get busy "fight" each other.

Disk I/O tends to be smaller blocksizes of a random nature.

Tape is sequential streaming as fats as it can read and write.

To write or read from tape effectively you need to allow it to spool up to its max speed without being interrupted by disk traffic. Otherwse you end up with the tape drive having to constantly back-hitch slowing down read and write.

Similarly when tape I/O is active it could delay your disk I/O's

Like most things IT, "it depends".